DESCRIPTION The objective of this training program in environmental toxicology is to produce scientists professionally qualified to make original research contributions directed at improved understanding of the impacts of hazardous chemicals and other environmental agents on human health, and to educate future generations of scientists with similar interests and qualifications. Special emphasis is placed on development and application of in vivo and in vitro experimental models and approaches designed ultimately to elucidate, in cellular and molecular terms, mechanisms through which such agents induce their adverse effects. These approaches are intended to provide information useful in the identification of health hazards created by the presence of these agents in the environment. Strong emphasis is also placed on the development, validation and application of methodology for detection and characterization of adverse effects that will improve assessment of actual or potential hazards to humans resulting from environmental exposures. Utilizing biochemical, chemical and biological approaches, the training of doctoral candidates and postdoctoral trainees is concerned with: characterization of effects of toxic, carcinogenic and mutagenic chemicals at the whole animal, tissue, cellular and molecular levels; development of chemical and biological methods for the detection and quantification of these effects in humans, experimental animals, and other experimental systems; studies of metabolic activation, macromolecular binding and genetic effects; and elucidation of modes of action at cellular and molecular levels. Training involves didactic courses, formal and informal seminars and other means of information exchange, and laboratory research projects utilizing appropriate model systems for problem definition and solution.